Xen devel - Sep 2007 - permit_access functionality

What is the exact use of ioport_permit_access() and irq_permit_access() kind of
functions? If I permit port/irq access to HVM guest for a particular port or
IRQ, does that mean guest VCPU does not issue a hypercall when accessing them?
If a PIRQ is asserted by physical hardware, can hvm guest directly get
notification if given such access?
 
Thanks
Jayant

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No, those functions are (currently) only for allowing I/O access for PV
guests. The recent VT-d patches provide direct I/O functionality for HVM
guests, if you have capable hardware.

 -- Keir

On 28/9/07 18:49, "Jayant Mangalampalli"
<Jayant_Mangalampalli@phoenix.com>
wrote:
> What is the exact use of ioport_permit_access() and irq_permit_access()
kind
> of functions? If I permit port/irq access to HVM guest for a particular
port
> or IRQ, does that mean guest VCPU does not issue a hypercall when accessing
> them? If a PIRQ is asserted by physical hardware, can hvm guest directly
get
> notification if given such access?
>  
> Thanks
> Jayant
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel


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